This invention relates to the conversion of primary saturated aliphatic and alicyclic amines having between 2 and 12 carbon atoms to oximes, comprising contacting said amine in a vapor phase with elemental oxygen and a catalyst comprising alumina or an oxygen-containing tungsten compound on a metal oxide support.
U.S. Pat. No. 4,337,358 (J. N. Armor) discloses a process for oxidizing primary saturated aliphatic and alicyclic amines by elemental oxygen to oximes, especially cyclohexylamine to cyclohexanone oxime, in the vapor phase using a silica gel catalyst and using temperatures of 120.degree. C. to 250.degree. C. and at atmospheric pressure.
Co-pending U.S. patent application Ser. No. 451,701 filed on an even date herewith and having co-inventors J. N. Armor, J. Yamanis, and E. J. Carlson discloses an improved catalyst comprising an oxygen-containing tungsten compound on alumina useful for production of oximes by selective oxidation, in the vapor phase, of saturated primary aliphatic and alicyclic amines such as cyclohexylamine with an elemental oxygen-containing gas; improved methods of preparation and regeneration of said improved catalyst are also disclosed.
A Japanese patent publication of July 11, 1972, having the No. SHO47-25324, relates to oxidation in liquid phase of primary aliphatic and alicyclic amines wherein a tertiary alcohol is present and preferably ammonia gas is present. A catalyst such as tungstic acid, phosphotungstic acid, molybdic acid, selenic acid, or selenious acid is preferably used. The highest conversions obtained in the examples are less than 20% and yields based on oxygen consumed are less than 50%.
U.S. Pat. No. 2,706,204 (K. Kahr) discloses that oximes are obtained by treating a primary amine, in the liquid phase, with hydrogen peroxide in the presence of a salt of an acid of tungsten, molybdenum or uranium as a catalyst.